[PATCH v5 20/20] tools: gpio: add debounce support to gpio-event-mon

From: Kent Gibson
Date: Thu Aug 27 2020 - 10:12:31 EST


Add support for debouncing monitored lines to gpio-event-mon.

Signed-off-by: Kent Gibson <warthog618@xxxxxxxxx>
---
tools/gpio/gpio-event-mon.c | 20 +++++++++++++++++---
1 file changed, 17 insertions(+), 3 deletions(-)

diff --git a/tools/gpio/gpio-event-mon.c b/tools/gpio/gpio-event-mon.c
index e50bb107ea3a..bd5ea3cc6e85 100644
--- a/tools/gpio/gpio-event-mon.c
+++ b/tools/gpio/gpio-event-mon.c
@@ -148,11 +148,12 @@ void print_usage(void)
" -s Set line as open source\n"
" -r Listen for rising edges\n"
" -f Listen for falling edges\n"
+ " -b <n> Debounce the line with period n microseconds\n"
" [-c <n>] Do <n> loops (optional, infinite loop if not stated)\n"
" -? This helptext\n"
"\n"
"Example:\n"
- "gpio-event-mon -n gpiochip0 -o 4 -r -f\n"
+ "gpio-event-mon -n gpiochip0 -o 4 -r -f -b 10000\n"
);
}

@@ -167,11 +168,12 @@ int main(int argc, char **argv)
unsigned int num_lines = 0;
unsigned int loops = 0;
struct gpio_v2_line_config config;
- int c;
+ int c, attr, i;
+ unsigned long debounce_period = 0;

memset(&config, 0, sizeof(config));
config.flags = GPIO_V2_LINE_FLAG_INPUT;
- while ((c = getopt(argc, argv, "c:n:o:dsrf?")) != -1) {
+ while ((c = getopt(argc, argv, "c:n:o:b:dsrf?")) != -1) {
switch (c) {
case 'c':
loops = strtoul(optarg, NULL, 10);
@@ -187,6 +189,9 @@ int main(int argc, char **argv)
lines[num_lines] = strtoul(optarg, NULL, 10);
num_lines++;
break;
+ case 'b':
+ debounce_period = strtoul(optarg, NULL, 10);
+ break;
case 'd':
config.flags |= GPIO_V2_LINE_FLAG_OPEN_DRAIN;
break;
@@ -205,6 +210,15 @@ int main(int argc, char **argv)
}
}

+ if (debounce_period) {
+ attr = config.num_attrs;
+ config.num_attrs++;
+ for (i = 0; i < num_lines; i++)
+ gpiotools_set_bit(&config.attrs[attr].mask, i);
+ config.attrs[attr].attr.id = GPIO_V2_LINE_ATTR_ID_DEBOUNCE;
+ config.attrs[attr].attr.debounce_period = debounce_period;
+ }
+
if (!device_name || num_lines == 0) {
print_usage();
return -1;
--
2.28.0